Shannon Channel Capacity
C = B · log₂(1 + S/N) — The fundamental limit on reliable communication
C = B · log₂(1 + SNR)
Bandwidth B
1 MHz
Signal Power S (dBm)
10 dBm
Noise Power N (dBm)
-90 dBm
--
Mbps capacity
SNR:
dB | SNR linear:
Technology
BW
Typ. Cap.
56K Modem
4 kHz
56 kbps
ADSL2+
2.2 MHz
24 Mbps
WiFi 6 (1ch)
80 MHz
600 Mbps
5G mmWave
400 MHz
4 Gbps
Move sliders to see capacity. The surface plot shows C(B, SNR). Note: doubling bandwidth always helps; doubling power only adds log₂(2)·B bits.